Unity dotNet IsValidEmail via http://nishantwork.wordpress.com/2012/10/11/how-to-validate-email-address-in-net-by-c/

IsValidEmail.cs

 /// <summary>
    /// Validate Email Address
    /// </summary>
    /// <param name="email"></param>
    /// <returns></returns>
    private static bool IsValidEmail(string email)
    {
        var r = new Regex(@"^([0-9a-zA-Z]([-\.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,9})$");

        return !string.IsNullOrEmpty(email) && r.IsMatch(email);
    }